code: def test_importable_with__OO():
      """
      When using -OO or export PYTHONOPTIMIZE=2, docstrings are discarded,
      this simple test may prevent something like issue #17970.
      """
      program = (
          "import matplotlib as mpl; "
          "import matplotlib.pyplot as plt; "
          "import matplotlib.cbook as cbook; "
          "import matplotlib.patches as mpatches"
      )
      cmd = [sys.executable, "-OO", "-c", program]
      assert (
          subprocess.call(cmd, env={**os.environ, "MPLBACKEND": ""})
          == 0
      )
  
file_path: matplotlib/lib/matplotlib/tests/test_matplotlib.py
imports: import os
  import subprocess
  import sys
  import pytest
  import matplotlib
label_desc: Use image node_id 5 for calling a global function with example usage: test_importable_with__OO() without return types